Blade-truing device.



J. R. THOMAS.

BLADE TRUING DEVICE.

APPLICATION FILED AUGJ, 1910.

Patented Feb. 28,1911;

3 SHEETS-SHEET 1.

wif/rss es J. R. THOMAS. BLADE TRUING DEVICE. APPLIGATION FILED AUGPI, 1910.

Patented Feb. 28, 1911.

J. R. THOMAS.

BLADE TRUING DEVICE.

APPLICATION FILED AUG. 1, 1910.

Patented Feb. 28, 1911.

3 SEEETSSHEET 3'.

UNITE STATES PATENT OFFICE.

JOHN R. THOMAS, OF ST. LOUIS, MISSOURI, ASSIGNbR TO HALL 86 BROWN WOODWORK- ING MACHINE C0,, ST. LOUIS, MISSbURI.

BLADE-TRUING DEVICE.

Specification of Letters Patent. PatentedFeb. 28, 1911.

Application filed August 1, 1910. Serial n. 574,933.

To all whom it may concern:

Be itknown that I, JOHN R. Tnonms, a citizen of the United States, residing at St. Louis. in the State of Missouri, have invented a new and useful Blade-Truing Device, of which the following is a specification.

My invention relates to improvements in the means of grinding or truing theseries of knives or cutters disposed in the rotating holder or cutter-head employed in that type of wood-working machine termed a planer.

Among others. the objects of the inventions aforesaid are (a) to provide a simple, detachable. and adjustable device by means of avhich the entire cutting edge of each ofthe series of blades is ground or trued simultaneously, in contra-distinction to those devices in which said cutting edge contacts with a traveling stone and is, in consequence, ground first at one point and then at another; (b) to prevent the burning or glazing of the truing stone; and (c) to provide means whereby said stone may be minutely leveled relative to the edge of the blades to be acted upon.

Other objects and advantages may be noted in the following specification and its 7 claims.

Like numerals refer to like parts throughout the accompanying drawings, in which- Figure 1 is an elevation, taken from the rear, of my completed device; Fig. 2 the reverse of Fig. 1; Fig. 3 a cross-section along line aeaz of Figs. 1 and 2, embracing a diagrammatic cross section of a cutterhcad and its cutters; Fig. 4 a perspective depicting a worm and worm gear of my device, and a section of a frame of the latter and its relation to said worm and gear; Fig. 5 a repetition of Fig. 2, taken from above in order to better depict the correlation of certain parts; Figs. 6, 7 and 8 elevations in perspective of certain correlated parts of my invention; and Figs. 9, 10 and 11 the reverse of Figs. 6, 7 and 8.

' In wood-planers as the lumber emerges from its treatment in the body of the machine it encounters a series of knives termed cutters which are being very rapidly rotated in aholder or cutter-head, the latplaner proper. The edge of said cutters is given the outline which it is desired to impart to the lumber, and hence it is necessary to the accomplishment of perfect work that each of the series of cutters be trued or ground identically alike in order that each may strike the lumber to the same depth and assume an equal share of the burden imposed. Again, it is desirable to be able to move the truing stone either into or out of contact with the revolving cutters, and the means for accomplishing this should be capable of automatically yielding where the operator lowers the stone too near the cutters, otherwise the contact is too severe and the edge of the blades may be damaged or ground too much or too rapidly. And further, it happens not uncommonly that a workman may neglect or be unable to set the stone perfectly square or level in its holder, in consequence of which one half of the edge of the cutters may be ground and the other half not contact with the stone at all. Therefore it is highly desirable to rovide a means for minutely adjusting or eveling the stone so that its whole truing edge may be thrown evenly in contact with the cutter edge.

In the practice ofmy invention I provide a comparatively heavy and rigid supporting frame 1 having feet 2 which rest upon projections of the frame of the planer. Supported in bearings 3 at opposite .inturned extremities of frame 1 is a secondary frame 4, upon an end of which is fixed a gear 5 which, in turn, engages the spirals of a worm 6 operated by crank -7. It is obvious that upon turning crank 7 gear 5 is caused to revolve and imparts a like motion to frame 4.

Detachably and slidably mounted upon, frame 4 is a carriage 8 whose external con-- formation, shown in Fig. 6, comprises a raised portion 9 defined by sharp, angular shoulders 10, the latter affording a track or guide, an upstanding apertured boss 11,

and an outstanding apertu'red lug 12. Slidof perfect work.

19 through which works screw 20, provided with nut 20, to find a bearing upon the top of boss 16., Holder 18, shown in Figs. 8 and 11, is pivoted at 21 to late '13 and said plate and holder are norma ly locked together by .so re-adjusted. Over the stone is fixed, by

screws 24, a fiat piece of steel 25 which assists set screw 26, laterally entering offset or shoulder 27 of holder 18, in maintaining the stone rigidly in place. Directed through the smooth aperture of lug 12 and engaging the threads'of lug 15 is a screw 28, having a shoulder 29, finding a bearing upon the top .of lug 12, and a cap 30, and about said screw and normally compressed by lugs 12 and 15 is a helical spring 31. Screw 28 vertically raises or lowers, at the will of the operator,

plate 13 and, in, consequence, the truing stone 18 and its holder 18, and should said stone be lowered too closely to the revolving cutters the latter will automatically push up the stone and parts 18 and 13, although a constant and proper contact will be maintained between the stone and cutters through the resistance of spring 31. For the movement of carriage 8 upon rotative frame 4 there is provided a lengthy threaded rod 32, provided with cap 33, a rest 34 for the fingers of the mechanic, and a spring 35 simulating the function of spring 31. Said rod works freely in the smooth bored lug 4 rising from frame 4, while engaging the treaded aperture of boss 11 of carriage 8, and upon rotating member 34 to the right or left carriage 8 and its accompanying parts 13, 18, and 18 are moved upon and toward one end or the other, as desired, of frame t.

A feature of my invention to which I attach great importance is the ability to rotate the truing stone above the cutters while the same are being ground. The cutter edges are usually beveled and when newly inserted in the cutter-head present fine, knife-like edges, whereas the width of the truing edge of the stone approximates f of an inch, and where in devices of this character the cutter edges are permitted to constantly contact with the stone at ene and the same point the latter soon burns or glazes or becomes uneven and incapable These disadvantages I overcome by being able to cause the cutters to start upon the stone from one of the longitudinal edges of the latter and thence, gradually or rapidly, pass completely across its entire surface to the opposite longitudinal margin, whereupon the whole operation may be repeated by turning crank 7 in the reverse direction. Likewise, myinvention of giving to the truing stone a design or pattern complementary tocthat of the cutter is highly valued, as therebythe entire edge of the latter is at once placed under the action of the stone, the truing accomplished most speedily, the work of the operator lessened, and no one part of the design of the cutters is in danger of being ground disproportionately to the other-of its parts, the stone acting in the capacity .of a mold or pattern.

'While I have hereinbefore describedmy invention in its application tothe cutters of a wood-planer, yet I do not wish to be understood as thereto confining said invention, and the right isreserved not only to use it in connection with other and different machines and to make such minor modifications therein as may from time to time be found necessary or convenient, but to substitute for the truing stone other and differ ent articles or tools for other and different purposes.

What I claim as new and desire to secure by Letters-Patent is 1. A blade truing device comprising a grinding stone, a stone-holder, a movable frame supporting said holder, members actuating said frame, and mechanism citeding reciprocal rotation of said stone across the line of contact therewith of the blades to be trued, whereby the latter are caused to progress from one to the other of the longitudinal margins of the truing edge of said stone, substantially as and for the purposes described.

2. A blade truing device comprising a grinding stone, a stone-holder, a movable frame supporting said holder, members actuating said frame, means for minutely levcling said stone relative to the edge of the blades to be trued, and mechanism effecting reciprocal rotation of said stone across the line of contact therewith of said blades, whereby the latter are caused to progress from one to the other of the longitudinal margins of the truing edge of said stone, substantially as and for the purposes described.

3. A blade truing device comprising a grinding stone, a stone-holder, a movable frame supporting said holder, members actuating said frame, means whereby the impact of the blades against said stone is yieldingly resisted, and mechanism effecting reciprocal rotation of said stone across the line of contact therewith of said blades, whereby the latter are caused to progress from one to the other of the longitudinal margins of the truing edge of said stone, substantially as and for the purposes described.

4. A blade truing device comprising a grinding stone, a stone-holder, a movable frame supporting said holder, members actuating said frame, means for the positive horizontal and vertical movement of said stone, and mechanism effecting reciprocal rotation of said stone across the line of contact therewith of the blades to be trued, whereby the latter are caused to progress from one to the other of the longitudinal margins of the truing edge of said stone, substantially as and for the purposes described. v

5. A blade truing device comprising a grinding stone, a stone-holder, a movable frame supporting said holder, members actuating said frame, means whereby said stone may be minutely leveled relative to the edge of the blades to be trued, means whereby the impact of said blades against said stone is yieldingly resisted, and mechanism effecting reciprocal rotation of said stone across the line of contact therewith of said blades, whereby the latter are caused to pro- 'gress from one to the other of the longitudinal margins of the truing edge of said stone, substantially as and for the purposes described.

6. A blade truing device comprising a grinding stone, at stone-holder, a movable frame supporting said holder, members actuating said frame, means whereby said stone maybe minutely leveled relative to the edge of the blades to be trued,-means for the positive horizontal and vertical movement of said stone, and mechanism efiecting recip rocal rotation of said stone across the line of contact therewith of said blades, whereby the latter are caused to progress from one to the other of the longitudinal marginsof the truing edge of said stone, substantially as and for the purposes described.

7. A blade truing device comprising a grinding stone, a stone-holder, a movable frame supporting'said holder, members actuating said frame, means whereby the impact of the blades against saidstone is yieldingly resisted, means for the positive horizontal and vertical movement of said stone, and mechanism effecting reciprocal rotation of said stone across the line of contact therewith of said blades, whereby the latter are caused to progress from one to the other of the longitudinal margins of the truing edge of said stone, substantially as and for the purposes described.

8. A blade truing device COIIIPIlSlllg a grinding stone, a stone-holder, a movable frame supporting said holder, members actuating said frame, means whereby the 1mpact of the blades against said stone 1s yieldingly resisted, means for the positive horizontal and vertical movement of said stone, means whereby said stone may be minutely leveled relative to the edge of said blades, and mechanism eflecting reciprocal rotation of said stone across the line of contact therewith of said blades, whereby the latter are caused to progress from one to the other of the longitudinal margins *of the truing edge of said stone, substantially as and for the purposes described.

JOHN R. THOMAS. Witnesses:

0. AUG. GRoTE, FRANK J. QUERTERMUS. 

